Abstract:
Purpose : Nitrogen (N) fertilizer is a major input in agro-ecosystems and has health, economic, and
environmental implications. Changes in the global N cycle has transgressed the ecological safe boundary
at present. Therefore, sustainable soil N management tools should be identified and implemented to reduce
environmental implications of agriculture. This review paper intends to describe the magnitude of the global N
based pollution, its health, economic, and environmental implications and suggest for approaches to achieve
sustainable soil N management.
Research Method : This paper shares a literature review on current efforts in optimizing soil N management. The
central topic is an on-farm experiment conducted in the University of Nebraska-Lincoln, USA that monitors and
manages in-season N in maize using a crop sensor technology. Other reliable findings from previously conducted
studies worldwide are presented as well.
Findings : Results of field studies revealed that there were no significant variations in maize grain yields
between sensor-based treatment and farmer’s business-as-usual treatment However, the crop sensorbased treatment recorded savings of N at an average rate of 32 kg/ha. Based on the reported findings in
literature, advanced fertilizer technology, manipulation of fertilizer application methods and development
of conceptual models to predict the crop N need are other potential tools to optimize N in agriculture.
Research Limitation : The behavior of reactive N in soil is unpredictable due to a complex interacting effect
of crop, soil, climatic and management factors.
Originality/ Value : In Sri Lanka as a country having a significant stake in agriculture, understanding and
adoption of some of these available new technologies for efficient N management will serve well in our
efforts for ecological sustainability.
